The Urban Dictionary T-Shirt

Same as *nix, with a missing asterisk usually resulting from laziness.

The abbreviation for a variation of Unix system including:
Linux, FreeBSD, NetBSD, Solaris, and even Apple's OSX.

An extremely scalable, simple yet intricate operating system that led a revolution in the computer world, creating a philosophy in itself and eventually dominating the world of servers.
"UNIX is basically a simple operating system, but you have to be a genius to understand the simplicity." - Dennis Ritchie
-from Stevie's definition of unix

The Urban Dictionary T-Shirt

To keep nix is an old english boarding school term for keeping a lookout. It is thought to derive from the word that was shouted by said lookout when a housemaster or teacher approached. Younger boys were instructed to "keep nix" while the older boys smoked, drank, buggered each other etc etc.

"I say Jenkins, will you keep nix while I roger young perkins there!"
"Nix!"
"Quick run here comes Mr Cooke"